The Price of Resonance

February's Valentine's Day cast a sweet yet restless atmosphere over Hogwarts. Pink decorations were everywhere, and owls busily delivered all sorts of cards and gifts. For most students, it was a day filled with anticipation, but for some, it was just another trouble to navigate carefully.

Snape showed utter disdain and avoidance towards this holiday. He left the Great Hall earlier than usual, curling up in library corners or empty Potions classrooms for longer periods, radiating an aura of "keep away" that was colder than the wind outside the castle. Lin Yanqing could sense that this pervasive collective emotion, with its strong emotional direction, made Snape extremely uncomfortable—a deep-seated aversion to external emotions he couldn't control.

However, the existence of the soul contract significantly diminished the effectiveness of this avoidance. The stabilized contract not only shared emotions but also amplified certain resonances unconsciously. When the Great Hall was filled with laughter and young boys and girls' hearts raced upon receiving gifts, Lin Yanqing could faintly sense Snape's amplified irritation; and when some bold girls tried to approach Snape, only to be repelled by his icy gaze and sharp words, Lin Yanqing could also share that moment of sharp rejection and... a faint trace of awkwardness that even Snape himself might not have noticed.

This forced emotional immersion left both of them exhausted. Lin Yanqing had to run Legilimency more frequently, building a barrier between himself and this ocean of emotions. Snape, on the other hand, became increasingly restless, like a beast trapped at the center of noise.

The atmosphere in the Potions class on Valentine's Day afternoon was particularly peculiar. Professor Slughorn was probably the only one who genuinely enjoyed the holiday; he had even lit some candles with a faint scent of love potion in the classroom (he emphasized it was absolutely safe, just to enhance the mood), which made quite a few students feel a bit giddy.

Today's lesson was about brewing a basic counter-curse potion to undo the effects of some low-level prank curses. At the workstations, Snape's movements were still precise, but Lin Yanqing could sense that his focus wasn't entirely on his work. It seemed part of his mind was resisting the interference of external emotional noise, while another part was... on guard.

His vigilance was not unfounded.

Just as Snape was about to add the final key ingredient—ground unicorn horn powder—to the cauldron, something unexpected happened!

It wasn't an obvious interference from James Potter, but a more hidden, more insidious method—through the contract, Lin Yanqing suddenly felt a strong, unfamiliar malicious emotion, like a poisoned needle, not aimed at Snape himself, but precisely at the counter-curse potion about to be successfully brewed before him! At the same time, his peripheral vision caught a Slytherin boy (Avery) behind and to the side quickly retracting his wand, a malicious, schadenfreude expression on his face.

It was a Silencing Charm! An extremely faint curse designed to disrupt the stability of the ingredients' magic power!

Snape had clearly also noticed the abnormal fluctuation of magic power within the cauldron. His expression instantly turned grim as he tried to force control, but the magic power, disturbed by the malicious curse, resonated with his own unsettled state, not perfectly calm due to external interference. Through the contract, Lin Yanqing clearly felt the sudden chaos in his magic power!

The potion in the cauldron began to bubble violently, its color shifting to an ominous dark gray, emitting a pungent odor—it was about to fail, and might even cause a small explosion!

At this critical moment, Lin Yanqing acted almost instinctively. He didn't try to help Snape stabilize the potion that had already lost control, but did something bolder and more direct—

He suddenly turned towards the Slytherin boy Avery, who had cast the curse. Before the other boy could retract the smug expression on his face, Lin Yanqing raised his wand, not to attack, but to unleash a nascent technique of Legilimency, which he had only recently mastered and required intense mental focus. Mixed with the full anger and precise targeting of this malicious interference, which he had shared from Snape through the contract, it was like an invisible mental shockwave, fiercely striking back!

Avery let out a short yelp, as if his brain had been sharply pricked by something. He stumbled back a step, crashing into the workstation behind him, knocking over his own cauldron and creating a mess. His face turned ashen, and he looked at Lin Yanqing in terror, as if he had seen a ghost.

He clearly hadn't expected that this usually gentle and quiet Ravenclaw would not only keenly detect his petty action but also launch such a precise and... counterattack with a strong Snape-like flavor!

Meanwhile, on Snape's side, because the source of the malicious interference was directly dealt with by Lin Yanqing in such an unexpected way, and because Lin Yanqing, while launching his counterattack, transmitted an extremely focused, calm, and goal-oriented combat emotion through the contract, it inadvertently helped him instantly stabilize his own chaotic state of mind. He seized this fleeting opportunity, flicked his wand, and cast several quick and precise remedial spells, forcefully stabilizing the potion on the verge of explosion. Although the quality of the finished product was greatly reduced and its color was murky, it at least didn't explode.

Merlin! Professor Slughorn hurried over, first looking astonished at the messy Avery, then at the barely successful, strangely colored counter-curse potion in Snape's cauldron, and finally his gaze fell on Lin Yanqing, who stood with his wand raised and a calm expression. What happened here?

Nothing, Professor. Lin Yanqing spoke first, his voice steady. Classmate Avery seemed to have made an operational error and knocked over his cauldron. I was startled by the commotion and instinctively raised my wand. My apologies. He perfectly played the role of an innocent bystander startled by an accident.

Avery opened his mouth, wanting to accuse Lin Yanqing of using dark magic (or something similar) on him, but he had no evidence, and having used a malicious curse himself first, he didn't dare speak up. He could only stand there, his face ashen, and miserably clean up the mess under Professor Slughorn's displeased gaze.

Snape remained silent from beginning to end. He stared intently at the strangely colored liquid in his cauldron, his chest rising and falling slightly. Through the contract, Lin Yanqing could feel his surging emotions, a mixture of lingering fear and anger. But this time, the spearhead of his anger was clearly directed at Avery, not at Lin Yanqing. Moreover, at the bottom of that anger, there was even a trace of... extremely rare, for Lin Yanqing's decisive and effective... approval.

This was a tacit understanding in battle. It had nothing to do with emotions, only survival.

The end-of-class bell rang like a pardon. Snape was the first to pack his things and left quickly. But as he passed Lin Yanqing, his steps paused almost imperceptibly. Something small and light slipped from his sleeve, falling into the shadow at Lin Yanqing's feet.

Only after everyone had left did Lin Yanqing bend down to pick up the object—it was a smooth, polished black stone, engraved with an ancient rune representing alliance in extremely fine strokes. The stone was cold, still carrying the warmth of Snape's fingertips.

This was not a potion ingredient, nor a research note.

It was a token. A cold, silent trophy and confirmation of an ally, belonging to Severus Snape.

He viewed this event of jointly confronting external malice as a successful alliance. And this stone was his commemoration and confirmation of it.

Lin Yanqing clenched the stone, its cold touch spreading from his palm.

He knew that the bond between them, after experiencing shared research, sharing, and even fighting side-by-side today, had become incredibly strong. It was no longer just a trouble or a tool; it had become their unique weapon and armor for survival in this castle full of open and hidden dangers.

The price was deeper emotional entanglement and risk, but the reward was an unparalleled, cold trust.

The Great Hall on Valentine's Day night was still noisy, but Lin Yanqing could feel that the soul connected at the other end of the soul bond, after the day's turbulence, though still cold, lacked a bit of the despair of fighting alone and had gained a bit of a dark, uncertain confidence of possession.